A method of producing a granular agrochemical composition having excellent handling properties, wherein a powdered agrochemical wettable composition or powdered agrochemical water-soluble composition is converted in form to a granular agrochemical composition, without altering the formulation thereof. The method of producing a granular agrochemical composition includes: treating a powdered agrochemical wettable composition or powdered agrochemical water-soluble composition by (1) a step of adding water, kneading, extruding and drying, (2) a step of adding water, granulating by stirring and drying, (3) a step of adding water, kneading and spray-drying, (4) a step of adding water and performing fluidized bed granulation, or (5) a step of pressure molding the powdered agrochemical wettable composition or powdered agrochemical water-soluble composition; followed by (a) a step of performing microgranulation by grinding, and if necessary, (b) a step of performing grain size regulation by sieving.